oxy patch updated on its way, stay tuned, page-24

I have spent countless hours crystallising stuff. Start with a solution that is close to, but not, saturated. Slowly concentrate the solution. Saturation limit is reached and the molecules fall out of solution. Too quick and you get precipitate (think kindy kids in playground). But if they fall out in an orderly fashion, you get crystals (think military parade). Either way, oxy is no longer available for transdermal delivery.

A small patch is nice and 3 days’ supply is fantastic but the problem is the solution may have been close to saturated. The patch sits on the shelf a while but however “sealed” it is, there is some level of evaporation. And one day, viola! we have crystals. Separation of oxy fr a TPM-oxy mix may be difficult but crystal harvesting is kid stuff…and oxy crystals are as pure as it gets.

In the lab, we used to joke that crystallisation was dependent on the phase of the moon – not the most reproducible of processes. Changing one component in the solution is enough to make the crystals appear/ disappear. Just because there are no crystals after a month does not mean that there won’t be any after a two. We see this in POH only realising there was a crystallisation problem a ways down the track. There is no easy way to speed up and still mimic the crystallisation conditions. Imo, POH did the right thing and waited it out. One interpretation of their announcements is in Sept they meant “for a given time period: crystals would have started growing in old formulation, so far no crystals in new formulation” and what they mean now is “no crystals for the shelf life of the patch”. As JM said, 100% sure.